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Working out Ohms and Power handling.
  #1  
Old 19-02-2012, 12:21 PM
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Default Working out Ohms and Power handling.

I'm thinking of building a BFM TLAH.

I'll be using 8 8ohm speakers each rated a 40W

How do I work out the total load and power handling.

My thinking is that If wired series/parallel then I'll get a 4 ohm load, but haven't got a clue how to work out the power handling?

Ta
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Old 19-02-2012, 12:32 PM
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The total power handling won't change Rob, regardless how you wire them - it'll still be 320W (8 x 40W).

With 8 x 8ohm speakers you'll be limited to 4ohm or 16ohm total impedance, so check your amp's output into each of those loads before deciding which to go for.

S.
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Old 19-02-2012, 01:13 PM
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Cheers Steve, Essentially it's for an install at work. We've moved the stage around so it's now in the corner of the room, looks great works very well, but a PITA for a drum monitor so we were toying with something like the HK elements system (we have the full 8.2KW version in house monster) but that would be a very expensive monitor. So I think this will work quite well.
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Old 19-02-2012, 07:01 PM
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http://basschat.co.uk/topic/167482-w...st__p__1532503
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Old 19-02-2012, 07:18 PM
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Quote:
Originally Posted by tauzero View Post
Am I missing something? I don't want to go through the visual rape process....

S.
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Old 19-02-2012, 09:18 PM
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If for whatever reason you prefer to have 8 ohm cabs, you can do 9 drivers per cab. You can then do 3 drivers in series, then 3 of those in parallel. Think of it as 3x3. That would be 9x40W = 360W per cab. Just sheer curiosity: do you have any particular driver in mind?
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Old 20-02-2012, 11:22 PM
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Quote:
Originally Posted by Thumper View Post
Am I missing something? I don't want to go through the visual rape process....
I was being idle. Here's the C&P, though it's probably not news to you:

An 8x10 at 4 ohms will be 8 8 ohm speakers wired up so that there are in effect two sets of four speakers. Each set will be four speakers in parallel and the two sets will be in series (or the equivalent). It would be possible to wire them so you could get one ohm, 4 ohms, or 16 ohms, with each speaker equally loaded. You could wire it up to give you about 9.5 ohms (two sets of three in parallel, one set of two in parallel, all in series) but you'd be loading the speakers a bit unevenly.
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Old 21-02-2012, 05:09 PM
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Purely in the interests of thoroughness, let's give it up for that most useful of all setups: 8 x 8, all wired in series = 64 Ohms!

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  #9  
Old 21-02-2012, 05:37 PM
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Here's a quick and basic look at two ways to wire a two speaker cab. You can add and divide if using multiple drivers (2, 4, 6, & 8) to get to the total ohms you need. In addition it's adding the total ohms, as in series, and division divides the ohms as in parallel, if that makes sense????

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Last edited by Cosmicrain : 21-02-2012 at 06:35 PM.
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